Do Preinstalled File get erased if I install new expansion packs?

[pboman]

Hello,  I have a PSR-SX900 that seems to have 1 GB space limitation in YEM to install other packs.  If I make a new install does it remove the packs that came preinstalled when it reformats the memory?  If so I would need to reinstall those packs also...  If the PSR-SX-900 has 4 GB of internal memory, why am I limited to only installing 1 GB worth of expansion packs through YEM?  I get an error message if I try to add all the packs that I have saying there is not enough space even though it only shows me trying to export 1.2 GB of file space...

[BogdanH]

Internal memory is used for styles,registrations, midi & audio recordings, pads, etc. Voice memory is separate place used only for voices. When you create a pack (for SX900), you will usually only be limited by number of voices in your installation file: their total size can be max 1GB. Number of styles doesn't really matter: 1st, they are small (compared to voices) and 2nd, they get installed in internal memory (4GB).

When you install ppi pack, complete previous pack is deleted: including pre-installed packs. If you like something in pre-installed packs, then you can download them at Yamaha web page (look at the bottom of the page) and then include individual styles/voices in your custom pack.
There's an option to install addition content to pack already installed in your keyboard -see qpi (Quick Pack Install) in manual- however, it doesn't work the way you probably expect.

Bogdan